Varan of the Nile

The Varan of the Nile ( Varanus niloticus ) is a lizard of imposing size of the family of the Varanidae.

Biology

Anatomy

The monitor of the the Nile has several particular adaptations.

It has two kinds of teeth: more pointed in front of the jaws and more punts with the back. Into growing old, pointed teeth are flattened to be able to crush the shells of Mollusques and other slow but well protected preys which form a greater part then its food.

The scale S of its skin are small, round and do not recover the close scales.

The members are well developed and allow the animal not to crawl that it is while going or while running.

Semi-watery, the monitor of the Nile is a very good swimmer and an adult can remain under water during more than one half an hour. The nostrils are placed to the top of cranium for better breathing on the surface. The tail is used as body of propulsion, being flattened vertically - but is also used to climb.

The language is used like olfactive Organe and is very sensitive.

It with the sense of smell in " stéréo" , i.e. each fork of the language detects the odors independently. Same manner that we can determine the direction of a sound thanks to our two ears, this monitor can know the direction of an odor with high degree of accuracy.

The body is of a color active of the dark gray to the black with yellowish spots. The cranium is barred of a black stripe to eye level. The yellow spots form 3 to 9 bands between the shoulders and the pelvis then is transformed into stripes over the entire length of the tail. The members are mottled, the belly is white or yellow with black stripes. There are albino individuals, who can sometimes be bought with a specialized importing stockbreeder/.

Food mode

The monitor of the Nile is a carnivorous opportunist and eats very different things according to its environment. In water, it nourishes Poisson S, of Crustacé S and molluscs. With ground, it catches insects and their larvae, molluscs, reptiles, Oiseau X and Mammifère S. Charognard, it eats of any meat, and it also sometimes happens to him to excavate in dustbins when it lives near the man. He is also fond of delicacies eggs of another large African reptile: the Crocodile of the Nile. Of course, the food also depends on its age. Small, he rather eats insects, larvae, fish and other small preys. While growing, it attacks other smaller reptiles (including other monitors, of the Nile or not), with eggs, the small birds and with the Rongeur S. Into growing old, it eats more and more preys slower like Gastéropode S, Bivalve S and shellfish. It snail raffole.

Natural distribution

The monitor of the Nile has a very broad distribution. One finds it in the valley of the Nile like on all the African Continent except for the arid areas of the Africa of the North-West (Morocco, Algérie, Libya, Tunisia, North of the Mali, the Mauritania, the Niger and the Chad). The monitors of the Nile do not have a habitat really preferably provided that there is water all the year. One as well finds them in the tropical forests, the Savane S, the Jungle S, the Marécage S, and even in edge of some Désert S.

Cut and Growth

The monitor of the Nile is largest African Lézard. It can reach more than 2 meters length, but generally does not exceed the 160 to 180 cm. Like other monitors, the male is generally taller than the female. The tail counts for more half the overall length. In spite of their length, these monitors are thus rather light, especially if one compares them with another African monitor - the Varan of savannas. So that a newborn of 30 cm reaches these monstrous proportions, it is necessary that it grows very quickly. A baby monitor of the Nile can, under favorable conditions, to double his length every 4-5 months. Into growing old, their growth decreases considerably, but the reptiles never stop growing completely.

Determination of the Sex

It is difficult to know the sex of a monitor of the Nile, because separately owing to the fact that the males are usually taller than the females, there are no really external differences. But sometimes the males show one or two of their Hémipénis, most of the time while déféquant, but also when they mark their territories. It there also sometimes two light bumps at the base of the tail formed by the sexual organs folded up just in lower part of the skin. As for the females, they lay sometimes unfertile eggs when they become adult. The majority of the monitors of the Nile captured are males, because they are more active and move more than the females in search of food.

Reproduction

Owing to the fact that the monitor of the Nile has a very vast distribution, being widespread in many different climates and two hemispheres, the time of the season of the loves varies much. For example, the majority of the monitors imported in the United States hatch at the beginning of our summer, but those of South Africa (which is located in the southern hemisphere) hatch in December. What does not vary, they is that the small monitors emergent in the season most favorable to their development - the beginning of the summer in more moderate climates, or the rain season in tropical climates. Some time after having copulated (surroundings one me captivity), the female of the monitor of the Nile will start has to seek a good place to lay its eggs. If possible, it will use a Termitière, which it breaks with its powerful claws in order to deposit the invaluable cargo inside. The termites attacks not the eggs, on the contrary, they stop the hole created by the mother. In this manner the eggs and the future babies monitors are safe from predatory. Moreover, the termitières have a temperature and constant moisture - a perfect place for the egg incubation of reptiles. If there is no termitière, the eggs are deposited in a burrow. In captivity, the eggs hatch in 140-165 days with 29°C with 30°C. It is probable that the wild eggs of monitors hatch in a similar time. These monitors can lay to 60 eggs, or half of the total weight of the female! After their birth, the small monitors separate and begin a solitary life.

Captivity

An ideal habitat for a monitor of the captive Nile is difficult to build, arrange, and maintain because of big size the animal, like its semi-watery nature. They can also be dangerous, being armed with powerful jaws of pointed teeth, sharp-edged claws, and a surprisingly strong tail and specifies - in addition to their defensive temperament. On the other hand this species adapts well to the captivity, is resistant to the diseases and the fluctuations of temperature, and can live about fifteen years. An animal born in captivity is a better choice, because it presents less risks to be infected internal parasites, and adapts better to the human contact. Unfortunately, almost all the monitors of the Nile which one finds in the trade are wild animals which were captured. When they are sold as having been born in captivity, they are generally hatched of collected eggs in kind. The only means of being sure is to buy it directly with a stockbreeder.

Housing

To be happy, a monitor of the Nile needs much place. Young people, they are of excellent climbing and a rather vertical habitat can be used to save place. But, while growing, they become increasingly terrestrial and they is necessary a space with horizontal more for them (while preserving some places to climb). Once adult, a monitor of the Nile should be placed in an external enclosure if the climate is suitable, or then in a part dedicated to its use.

It is completely false to think that a monitor will not grow if it is kept in a too small habitat, as he is sometimes heard. The only things which will be accomplished by keeping it in such a situation are muscular problems and Os seux. It is also very cruel for the animal in question.

water

Being Semi-watery, the monitor of the Nile needs not only fresh water for drinking, but should also be able to bathe. At the time of the , the died skin with need moults to be wet for good to fall apart. A rather large container so that it can be immersed completely is thus necessary. If possible, it is preferable to provide a basin of a sufficient size so that it can swim. These monitors have the practice of déféquer in water, which is in fact rather convenient, since water is changed daily, and when waste is seen. To humidify the habitat, it is possible to place water close to a source of heat.

A container practices, economic and of good dimensions for youthful is a case with litter of cat. Adult, one will need something for less the size of a bath-tub.

References

BENNETT, D. 1998: Lizards monitor. Natural history, biology & husbandry. Warlich. Germany.

FAUST, R.J. 2001: Nile monitors: everything butt history, care, nutrition, handling, and behavior. Barron' S. Hauppauge, NY.

English
: Little Book off Monitor Lizards

French
: C.I.T.E.S.

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